Chronic obstructive pulmonary disease (COPD) is the most common chronic disease of the airways that is caused in 90 % of cases by smoking. COPD is a preventable and treatable disease. However, many patients do not know that they suffer from the disease, so the number of unreported cases of patients is very high. In this article, you will find important information on the epidemiology, etiology, pathophysiology and diagnosis, as well as the differential diagnosis and treatment of COPD.

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that we use for monitoring patients to seeing
how they are doing. So how do patients withCOPD present its breathlessness on exertion,
and the level of exertion necessary to makethem breathless would tell you how severe
the disease is. So for example, you have apatient that says I can walk on the flat for
miles and miles, but if I try and walk upa steep hill, I find it very difficult and
gasp and have to stop half way up. I suggestthey have relatively mild disease that allows
them to do most everyday life things, butonly detectable to them when they do severe
exertion. However, the more severe patientwill say, “I will get breathless when I
will walk a hundred yards”, and many ofthe patients which I see in my clinic are
not able to walk more than 50, 60, 70 yards,before they have to stop to catch their breath,
and some will be breathless walking betweenthe bedroom and the bathroom. This degree of
dyspnoea is a chronic background situationwhere there are fluctuations and this actually
happens on a day to day basis. It's not clearwhy, it has probably to do with the weather and pollution
levels, but patients will have a bad day andthen followed by a good few days. As well as
breathlessness, the other commonsymptom is a cough and that is usually productive
of dirty looking, grey black phlegm, it couldbe white as well. That's the chronic bronchitis,
and that reflects the increase in the mucousglands and the hyperplasia of those glands producing
more mucous due to the cigarette smoke inducedinflammation. And chronic bronchitis is defined
as 'daily cough with sputum productionthat lasts for at least 3 months and for two
years in a row'. Other symptoms that patientsget, they can get a wheezy chest, they occasionally
cough up a little bit of blood. They get variousaches and pains in their chest because of
the coughing and the breathlessness pullingon the muscles and the ribs during respiration.
With bad disease, developing cor pulmonaleto chronic hypoxia, they'll have ankle oedema.
And patients with chronic hypoxia and severeairways obstruction will feel tired, they'll
lose energy, and some patients actually dohave gradual weight loss, and can get to the
level of having cachexia. If they developtype 2 respiratory failure or a rise in PCO2,
that's associated with morning headaches anddrowsiness. An important thing about COPD
is that many patients, not all, also haveacute deteriorations. And these are sustained
increases in severity of the illness, andthey last a few days to a few weeks. They
are usually precipitated by a viral infectionbut they can occur for other reasons, which are
not clear. Some patients don't get exacerbations,they are non-exacerbators, they have chronic
breathlessness, but they don't change withtheir degree of the breathlessness. Other
patients exacerbate infrequently once everyyear or two, once every few months, and there
are other patients who exacerbate very frequently,as often as very few weeks. And these exacerbations are
quite often severe enough to require hospitalization.
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As I said, they are frequently precipitated
by a viral or bacterial infection, but notalways. So how do you recognize the exacerbation?
Well the patient may have viral upper respiratorytract infection, symptoms of sore throat, a
bit of a runny nose, and then develop a bitof a cough. And with that cough, they start
to produce more phlegm and becomes a bacterialinfection, the phlegm will go green and thick
and that’s a marker of active bacterialinfection of the bronchiole. And as that happens,
the patient gets increasing dyspnoea, theirnormal exercise tolerance falls, they are
less able to do what they should be able todo normally, and the cough will increase,
and there may be a fall in their lung functionmarkers that keep flow in the FEV1, but not
always. Patients with severe COPD, their FEV1will be about 0, 0.8 and an exacerbation may
not change that much at all. What are the

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